Efim G. Evseev

Ben-Gurion University of the Negev, Be'er Sheva`, Southern District, Israel

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Publications (22)26.13 Total impact

  • Avraham I. Kudish, Efim G. Evseev
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    ABSTRACT: The erythemal UVB and UVA irradiance monitored at Beer Sheva, Israel from June 1994 through March 2012 has been analyzed. A statistical analysis was applied to the daily values for each month and average, median, standard deviation, coefficient of variation (%), maximum and minimum values are reported. The maximum and minimum monthly average daily values for both erythemal UVB and UVA occur in June and December, respectively. They are 1.658 Wm−2(ER) and 0.346 Wm−2(ER) for the case of erythemal UVB and the corresponding values for UVA are 300.78 Wm−2 and 135.52 Wm−2. A similar statistical analysis was performed on the monthly average daily values throughout the time interval of this study. In addition, the monthly average daily values were analyzed to determine if there existed any trends for the individual months. A linear regression analysis was applied to the monthly average daily erythemal UVB and UVA irradiance as a function of year. No statistically significant trends were observed, based upon the corresponding p-values; a possible exception being the UVA irradiance during February, which may have a slight negative trend. Typical erythemal UVB and UVA irradiance meteorological years were developed for Beer Sheva and its environs.
    Renewable Energy. 01/2014; 63:84–89.
  • Avraham I Kudish, Marco Harari, Efim G Evseev
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    ABSTRACT: The composition of the incident solar global ultraviolet B (UVB) radiation with regard to its beam and diffuse radiation fractions is highly relevant with regard to outdoor sun protection. This is especially true with respect to sun protection during leisure-time outdoor sun exposure at the shore and pools, where people tend to escape the sun under shade trees or different types of shading devices, e.g., umbrellas, overhangs, etc., believing they offer protection from the erythemal solar radiation. The degree of sun protection offered by such devices is directly related to the composition of the solar global UVB radiation, i.e., its beam and diffuse fractions. The composition of the incident solar global UVB radiation can be determined by measuring the global UVB (using Solar Light Co. Inc., Model 501A UV-Biometer) and either of its components. The beam component of the UVB radiation was determined by measuring the normal incidence beam radiation using a prototype, tracking instrument consisting of a Solar Light Co. Inc. Model 501A UV-Biometer mounted on an Eppley Solar Tracker Model St-1. The horizontal beam component of the global UVB radiation was calculated from the measured normal incidence using a simple geometric correlation and the diffuse component is determined as the difference between global and horizontal beam radiations. Horizontal and vertical surfaces positioned under a horizontal overhang/sunshade or an umbrella are not fully protected from exposure to solar global UVB radiation. They can receive a significant fraction of the UVB radiation, depending on their location beneath the shading device, the umbrella radius and the albedo (reflectance) of the surrounding ground surface in the case of a vertical surface. Shading devices such as an umbrella or horizontal overhang/shade provide relief from the solar global radiation and do block the solar global UVB radiation to some extent; nevertheless, a significant fraction of the solar global UVB radiation does penetrate this supposedly 'protective or comfort zone'. As a result, it is imperative to either apply sunscreen or cover up the exposed body surfaces even when under such shading devices.
    Photodermatology Photoimmunology and Photomedicine 10/2011; 27(5):236-44. · 1.52 Impact Factor
  • Avraham I Kudish, Marco Harari, Efim G Evseev
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    ABSTRACT: The broad-band normal incidence UVB beam radiation has been measured at Neve Zohar, Dead Sea basin, using a prototype tracking instrument composed of a Model 501A UV-Biometer mounted on an Eppley Solar Tracker Model St-1. The diffuse and beam fraction of the solar global UVB radiation have been determined using the concurrently measured solar global UVB radiation. The diffuse fraction was observed to exceed 80% throughout the year. The application of the results of these measurements to the possible revision of the photoclimatherapy protocol for psoriasis patients at the Dead Sea medical spas is now under investigation. The suggested revision would enable the sun-exposure treatment protocol to take advantage of the very high diffuse fraction by allowing the patient to receive the daily dose of UVB radiation without direct exposure to the sun, viz. receive the diffuse UVB radiation under a sunshade. This would require an increase in sun-exposure time intervals, as the UVB radiation intensity beneath a sunshade is less than that on an exposed surface.
    Photochemistry and Photobiology 01/2011; 87(1):215-22. · 2.29 Impact Factor
  • Avraham I. Kudish, Efim G. Evseev
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    ABSTRACT: Incident solar radiation (insolation) is attenuated by two different phenomena, (i) atmospheric scattering by air molecules, water vapor and aerosols, and (ii) atmospheric absorption by ozone, water and carbon dioxide. The degree of terrestrial solar radiation attenuation is a function of its optical path length, i.e., the distance the Sun’s ray traverse through the Earth’s atmosphere prior to being incident on the its surface. The attenuation by atmospheric scattering, irrespective of source, is an inverse function of the wavelength. Absorption of insolation in the atmosphere is due mainly to ozone in the ultraviolet range and water vapor in the infrared range of the solar spectrum. Ozone absorption decreases with increasing wavelength and above 350 nm there is no absorption. Thus, a priori, any changes in either the ozone layer thickness (OLT) and/or aerosol optical density (AOD) will have a greater effect on ultraviolet radiation, in general, and on UVB in particular. An empirical correlation that determines the UVB radiation intensity as a function of solar global radiation, OLT, AOD and optical path length as represented by the air mass is presented and validated by an independent database. In addition, a parameter sensitivity study was performed on the empirical correlation using two different methods. The application of the empirical correlation as a function of hour type (i.e., clear, partially cloudy and cloudy) was also investigated.
    Renewable Energy. 01/2011; 36(6):1854-1860.
  • Efim G. Evseev, Avraham I. Kudish
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    ABSTRACT: A model to convert horizontal solar global radiation to that on a tilted surface is presented. It is based upon a relatively simple model proposed by [Olmo FJ, Vida J, Foyo I, Castro-Diez Y, Alados-Arboledas L. Prediction of global irradiance on inclined surfaces from horizontal global irradiance. Energy 24 (1999) 689–704]., which requires only measurements of horizontal solar radiation but was found to produce significant errors when tested with data from another site. The present model assumes the availability of databases for at least two of the three solar radiation types, viz., global, beam and diffuse. The horizontal global radiation is converted to that on a tilted surface by applying the Olmo model to the diffuse component, whereas the beam component is converted by using the geometrical relationship between the two surfaces. The original Olmo anisotropic radiation correction factor is now assumed to be a function of sky conditions. The solar radiation databases were converted to subsets corresponding to clear, partially cloudy and cloudy sky based upon clearness index values. The three anisotropic correction factors were determined by fitting to a 12-months database. The present model was then tested by applying it to a second database consisting of 24-months not involved in the model development. It was found to give better results than three highly regarded more complex models.
    Renewable Energy. 01/2009; 34(1):112-119.
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    Efim G. Evseev, Avraham I. Kudish
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    ABSTRACT: Global and diffuse solar radiation intensities are, in general, measured on horizontal surfaces, whereas stationary solar conversion systems (both flat plate solar collector and PV) are tilted towards the sun in order to maximize the amount of solar radiation incident on the collector surface. Consequently, the solar radiation incident on a tilted surface must be determined by converting the solar radiation intensities measured on a horizontal surface to that incident on the tilted surface of interest. There exist a large number of models designed to perform such a conversion. 11 such models have been tested utilizing data measured in Beer Sheva, Israel. The data consist of hourly global and diffuse solar radiation on a horizontal surface, normal incidence beam and global radiation on a south-oriented surface tilted at 40°. The horizontal diffuse radiation measured using a shadow ring was corrected using four different correction models. This resulted in 44 model permutations. The individual model performance is assessed by an inter-comparison between the calculated and measured solar global radiation on the south-oriented surface tilted at 40° using both graphical and statistical methods. The relative performance of the different models under different sky conditions has been studied. Different grading systems have been applied in an attempt to score the relative performance of the models.
    Solar Energy - SOLAR ENERG. 01/2009; 83(3):377-388.
  • Avraham I. Kudish, Efim G. Evseev
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    ABSTRACT: Solar global and diffuse radiation intensities are, in general, measured on horizontal surfaces, whereas stationary solar conversion systems (both flat plate solar collector and PV) are tilted towards the sun in order to maximize the amount of solar radiation incident on the collector surface. Consequently, the solar radiation incident on a surface tilted to the south (northern hemisphere) must be determined by converting the solar radiation intensities measured on a horizontal surface to that incident on the tilted surface of interest. There exist a large number of models designed to perform such a conversion. Eleven such models have been tested utilizing data measured in Beer Sheva, Israel. The data consist of hourly solar global and diffuse radiation on a horizontal surface, normal incidence beam and global radiation on a south-oriented surface tilted at 40°. The individual model performance is assessed by an inter-comparison between the calculated and measured solar global radiation on the south-oriented surface tilted at 40° using both graphical and statistical methods. The relative performance of the different models under different sky conditions, i.e., clear, partially cloudy and cloudy as defined by the hourly clearness index value, has been studied.
    Proc SPIE 08/2008;
  • Avraham I. Kudish, Efim G. Evseev
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    ABSTRACT: The measurement of the diffuse radiation incident on a horizontal surface, a priori a straightforward task, is fraught with difficulties. It is possible to measure the diffuse radiation by three different techniques: two of which measure it directly and the third indirectly. The most accurate is the indirect one, which is based upon the concurrent measurements of the horizontal global and the normal incidence beam radiation. The disadvantage of this being the relatively expensive tracking system required for measuring the latter. The diffuse radiation can be measured directly with a pyranometer outfitted with either an occulting disk or shadow ring, which prevent the beam radiation from impinging on the pyranometer sensor. The occulting disk can provide accurate measurements of the diffuse radiation but it requires a relatively expensive sun tracking system in the east–west axis. The shadow ring is a stationary device with regard to the east–west axis and blocks the beam radiation component by creating a permanent shadow on the pyranometer sensor. The major disadvantage of the shadow ring is that it also blocks that portion of the diffuse radiation obscured by the shadow ring. This introduces a measurement error that must be corrected to account for that portion of the sky obscured by the shadow band. In addition to this geometric correction factor there is a need to correct for anisotropic sky conditions. Four correction models have been applied to the data for Beer Sheva, Israel and the results have been evaluated both graphically and statistically. An attempt has been made to score the relative performance of the models under different sky conditions.
    Solar Energy - SOLAR ENERG. 01/2008; 82(2):144-156.
  • Avraham I. Kudish, Efim G. Evseev
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    ABSTRACT: The measurement of the horizontal diffuse radiation, a priori a straightforward task, is fraught with difficulties. It is possible to measure the diffuse radiation by both direct and indirect methods. The most accurate method is probably the indirect one, which utilizes concurrent measurements of the horizontal global and the normal incidence beam radiation. The disadvantage of this method is the relatively expensive tracking system required for measuring the latter. The diffuse radiation can be measured directly with a pyranometer outfitted with either an occulting disk or shadow ring, which prevent the beam radiation from impinging on the pyranometer sensor. The former method can provide accurate measurements of the diffuse radiation but requires a relatively expensive sun tracking system in the east-west axis. The shadow ring is a stationary device with regard to the east-west axis and blocks the beam radiation component by creating a permanent shadow on the pyranometer sensor. The disadvantage of the shadow ring is that it also blocks a portion of the sky, which necessitates a geometrical correction factor. There is also a need to correct for anisotropic sky conditions. Four correction models have been applied to the data and the results evaluated and ranked.
    Proc SPIE 10/2007;
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    ABSTRACT: Solar global radiation is a function of solar altitude, site altitude, albedo, atmospheric transparency and cloudiness, whereas solar global radiation on a clear day is defined such that it is a function of all the abovementioned parameters except cloudiness. Consequently, analysis of the relative magnitudes of solar global radiation and solar global radiation on a clear day provides a platform for studying the influence of cloudiness on solar global radiation. The Iqbal filter for determining the day type has been utilized to calculate the monthly average clear day solar global radiation at three sites in the Negev region of Israel. An inter-comparison between four models for estimating clear sky solar global radiation at the three sites was made. The relative accuracy of the four models was determined by comparing the monthly average daily clear sky solar global radiation to that determined using the Iqbal filter. The analysis was performed on databases consisting of measurements made during the time interval of January 1991 to December 2004. The monthly average daily clear sky solar global radiation determined by the Berlynd model was found to give the best agreement with that determined using the Iqbal filter. The Berlynd model was then utilized to calculate a daily clear day index, Kc, which is defined as the ratio of the daily solar global radiation to the daily clear day solar global radiation. It is suggested that this index be used as an indication of the degree of cloudiness. Linear regression analysis was performed on the individual monthly databases for each site to determine the correlation between the daily clear day index and the daily clearness index, KT.
    Energy Conversion and Management - ENERG CONV MANAGE. 01/2007; 48(1):259-268.
  • A. I. Kudish, E. G. Evseev
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    ABSTRACT: The Dead Sea basin is located at the lowest terrestrial site on the earth and, thereby, has the tallest atmospheric air column above its surface. Consequently, the Dead Sea basin is expected, a priori, to have the highest terrestrial barometric pressure and, thereby, the highest molecular oxygen density on the earth. The barometric pressure and dry bulb temperature have been monitored continuously at Neve Zohar, located on the western shore of the Dead Sea, since January 1995. The monthly average daily barometric pressure values exceed normal atmospheric pressure by a maximum of 4.83 hPa (4.77%) and a minimum of 33.1 hPa (3.26%) for December and July, respectively. This increase in barometric pressure can serve as a simple way to improve arterial oxygenation in hypoxemic patients. As a result, a number of research projects have been initiated on the treatment of patients suffering from pulmonary and cardiac diseases at the Dead Sea basin. The hourly barometric pressure data with regard to both its diurnal and monthly variation and the correlation between barometric pressure and dry bulb temperature will be analyzed.
    Theoretical and Applied Climatology 01/2006; 84(4):243-251. · 1.76 Impact Factor
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    ABSTRACT: A statistical analysis and inter-comparison of the solar UVB, UVA and global radiation for Beer Sheva and Neve Zohar (Dead Sea) are presented utilizing data measured from January 1995 through December 2002. Beer Sheva is located approximately 65km to the west of and 700m above Neve Zohar. The monthly average hourly and daily values for all radiation types at both sites are reported. The standard errors of the monthly average daily values have been calculated in order to ascertain whether the average daily radiation intensities are representative, i.e. if the magnitude of the standard error is less than the inherent measurement uncertainty of the instruments, and, thereby, justify an inter-comparison between the two sites. The relative magnitude of the global, UVB and UVA radiation intensity at the two sites is attributed to the enhanced scattering of the incident solar radiation at the Dead Sea location due to the longer optical path length it must traverse to arrive at the Dead Sea, the lowest terrestrial point on earth. The degree of attenuation of solar radiation due to the scattering phenomena is inversely proportional to the wavelength raised to some power and, consequently, it is greatest for UVB and negligible for global radiation.
    Theoretical and Applied Climatology 01/2005; 80(1):1-15. · 1.76 Impact Factor
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    ABSTRACT: An inter-comparison of the clearness indices for the solar UVB, UVA and global radiation for Beer Sheva and Neve Zohar (Dead Sea) are presented utilizing radiation data measured from January 1995 through December 2001 for which there is a one-to-one correspondence between the measurements, viz., any day for which a hourly value for one of the sites was missing is rejected and not included in the analysis for that particular radiation type. Beer Sheva is located ca. 65 km to the west and is approximately 700 m above Neve Zohar, which is located on the western shore of the Dead Sea. The Dead Sea is the lowest terrestrial point on the earth, approximately 400 m below mean sea level. The relative magnitudes of the global, UVB and UVA radiation intensities at the two sites can be attributed to the enhanced scattering at the Dead Sea due to the longer optical path length the solar radiation must traverse at the Dead Sea. The degree of attenuation due to scattering phenomena is inversely proportional to the wavelength raised to some power and, consequently, it is greatest for UVB and very small for global radiation. The UVB and UVA solar constants were determined from the extraterrestrial radiation values tabulated by Fröhlich and Wehrli [Spectral distribution of solar irradiance from 25000 nm to 250nm, in: M. Iqbal, An introduction to solar radiation, Academic Press, New York, 1981, Appendix C, pp. 380–381]. The clearness indices for global and UVA radiation were of similar magnitude, whereas those for UVB radiation were of two orders of magnitude smaller. In addition, the monthly average hourly UV Index at both sites has also been determined and an inter-comparison of the values has been performed for all available hourly values from January 1995 through August 2002 for both sites. It is observed that the monthly average hourly UV Index values at the Dead Sea are never in the extreme range.
    Energy. 01/2004;
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    ABSTRACT: A solar desalination system consisting of a solar collector coupled to an evaporation/condensation chamber, all components fabricated from polymeric materials, has been developed and tested. A simulation model of the desalination system has been developed and validated by inter-comparison with experimental measurements on such a system. The simulation model employs a numerical solution to a set of differential equations describing the system. The validated simulation model was then utilized to perform parametric sensitivity studies to determine optimum design parameters and operation conditions. It was found that a solar desalination system, based upon the prototype studied, is capable of producing in excess of 11 kg m−2 d−1 of distillate on a sunny day when the gap between the evaporator and condenser surfaces is of the order of 2 cm, and the feedstock flow rate is within the range of 40–50 kg m−2 d−1. Such a corrosion resistant desalination system would be ideal for desalination of seawater. The results of the performance testing, simulation model validation and parametric sensitivity studies on the prototype module are reported.
    Energy Conversion and Management 06/2003; 44(10):1653–1670. · 2.78 Impact Factor
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    ABSTRACT: An experimental study and a simulation model describing a coaxial tubular solar collector fabricated from polymeric materials, consisting of an inner black tube as a solar energy absorber in intimate contact with an outer transparent tube as an insulator, having the potential to provide low grade thermal energy at reasonable costs is reported. The simulation model describes the transient performance of the coaxial tubular polymeric solar collector utilizing non-linear equations solved by a difference splitting technique. The simulation model was first validated utilizing the experimental data and was then used to determine the optimal design parameters, viz. the inner, black absorber, and outer, transparent insulator, tube thicknesses. In addition, the effect of an annular air filled gap between the coaxial tubes on system performance was also studied. The results of the experimental and simulations studies are reported together with the optimal design specifications.
    Energy Conversion and Management 01/2003; 44(16):2549-2566. · 2.78 Impact Factor
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    ABSTRACT: A simulation model describing a solar collector containing a selectively coated, polymeric, double walled absorber plate with parallel fluid flow channels has been developed and validated utilizing experimental data from such a solar collector module. The simulation model contains a more refined radiative energy balance, which takes into consideration the fact that the glazing may not be totally opaque to long wavelength radiation, and is solved by applying numerical integration to the non-linear differential equations that describe the system. The validated simulation model was then utilized to perform parametric sensitivity studies on the system heat transfer coefficients, collector efficiency factor, outlet temperature of the heat exchange fluid and average daily efficiency with regard to (i) mass flow rate for the heat exchange fluid; (ii) type of glazing, viz., glass, polymer film and double walled polymeric plate; (iii) channel height of double walled structure used as the absorber plate; and (iv) effect of the air gap thickness between the absorber plate and the glazing on the overall heat transfer phenomena.The daily performance tests on the solar collector modules exhibited average daily efficiencies in the range of 50–60% and maximum outlet heat exchange fluid temperatures in excess of 60°C. Such corrosion resistant selectively coated absorber plates would be ideal for heating the feedstock for desalination of seawater in an evaporation–condensation process. The results of these analyzes are reported in detail.
    Energy Conversion and Management 03/2002; 43(5):651–671. · 2.78 Impact Factor
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    ABSTRACT: Global and normal incidence radiation intensities measured at two sites located in the semi-arid Negev region of Israel have been utilized to develop a set of monthly empirical regression equations for determining the diffuse radiation that simulate the data shown graphically in the classic paper by Liu and Jordan. This equation expresses K d , the ratio of the daily diffuse on a horizontal surface to the daily extraterrestrial radiation on a horizontal surface, as an exponential function of K D , the ratio of the daily beam on a horizontal surface to the daily extraterrestrial on a horizontal surface. The databases utilized in developing the equations consisted of measurements made in Beer Sheva and Sde Boker during the years 1990–1998 and 1990–1999, respectively. The monthly empirical regression equations were validated by using an independent set of data measured in Beer Sheva during the years 1983–1989. It was observed that a single set of monthly equations was capable of characterizing the Negev region of Israel. The statistical analysis of the results is presented and discussed in detail.
    Theoretical and Applied Climatology 08/2001; 69(3):213-220. · 1.76 Impact Factor
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    A I Kudish, E Evseev
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    ABSTRACT: Statistical relationships between the hourly radiation intensity values of both ultraviolet-B (UVB) and ultraviolet-A (UVA), and of the corresponding global radiation at two sites in Israel, the Dead Sea and Beer Sheva, are presented using radiation data measured from January 1995 to January 1999. It was determined, based upon the square of the correlation coefficient (r 2), that in the case of the UVB, a quadratic equation provided a better fit of the database, whereas in the case of UVA, a linear equation was sufficient, i.e. no significant improvement in r 2 was obtained using a quadratic equation. Each monthly empirical equation was tested by utilizing measurements from a single month of independent observations. The accuracy of the individual equations was determined by calculating the mean bias error (MBE), the root mean square error (RSME) and the percent coefficient of variation (CV). The results of this statistical analysis showed that, at both sites, the UVA relationships were characterized by a CV of B10%, with the exception of a single month. In the case of the UVB correlations, the CV values exceeded 10% for more than 75% of the year, both at the Dead Sea and at Beer Sheva. CV values of \20% were observed for more than a third of the individual months at both the Dead Sea and Beer Sheva. Monthly and seasonal relationships from one site were then tested by applying them to the second site. In both cases, the relationships between both UVA and UVB and global radiation were found to be site-specific. On the basis of this statistical analysis, the UVA relationships were found to be far superior predictors than the corresponding UVB ones. In fact, the UVB relationships have limited applicability for predicting UVB from the corresponding global solar radiation intensity. Copyright © 2000 Royal Meteorological Society.
    International Journal of Climatology 01/2000; 20:759-770. · 2.89 Impact Factor
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    ABSTRACT: A method for the characterization and inter-comparison of sites with regard to their suitability for utilization of solar energy based upon the statistical analysis of their solar radiation intensities is presented. In this method each monthly data set of the daily global, horizontal beam and diffuse radiation intensities was analyzed and the following parameters were determined: monthly average daily radiation intensity, coefficient of variation, skewness and kurtosis. The values of the skewness and kurtosis have been applied, using generally accepted rules, to describe the distribution curves for each of the radiation intensity data sets. In addition, the same type of statistical analysis was applied to the monthly average daily ratios of the horizontal beam to global radiation, diffuse to global and the clearness index for the three sites. In this investigation, this statistical analysis method has been applied to the global and beam radiation measured at three sites located in the southern, Negev region of Israel, viz., Beer Sheva, Sde Boker and Eilat. The southern region of Israel is characterized by relatively high average daily irradiation intensities for both global and normal incidence radiation. They have been characterized with regard to the distribution of their intensity levels and a site inter-comparison has also been performed. An inter-comparison of the results of these analyses for the three sites has been performed on a monthly basis. The results of this analysis are used both to characterize and compare the composition of the solar radiation at the three sites under investigation. The results of this study will be presented in detail.
    Solar Energy - SOLAR ENERG. 01/2000; 69(4):283-293.
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    ABSTRACT: The Dead Sea basin offers a unique site to study the attenuation of the ultraviolet (UV) radiation, as it is situated at the lowest point on Earth, about 400 m below sea level, and the air above the Dead Sea is characterized by a relatively high aerosol content due to the very high salt content of the Dead Sea. In view of its being an internationally recognized centre for climatotherapy, it is of interest to study both its UV intensity and attenuation as a function of wavelength relative to other sites. In order to provide a basis for intercomparison of the radiation intensity parameters measured at the Dead Sea, a second set of identical parameters were being measured simultaneously at a second site, located at a distance of ca. 65 km and to the west and situated above sea‒level (Beer Sheva at +315 m a.s.l.). The ultraviolet radiation, both UV‒B and UV‒A, were monitored continuously at both sites using Solar Light Co. Inc. broad‒band meters. In addition, sporadic measurements utilizing a narrow‒band spectroradiometer were performed to ascertain the extent of site‒specific spectral selectivity in the ultraviolet spectrum. The monthly average daily attenuation rates were found to vary from −10·2 to −17·3 per cent 1000 m−1 and −3·3 to −8·7 per cent 1000 m−1 for UV‒B and UV‒A, respectively. The average monthly values for UV‒B and UV‒A are −14·6 per cent 1000 m−1 and −5·4 per cent 1000 m−1, respectively. These values are in the range of values reported previously for studies performed at high altitudes, e.g. in the Alps and the Andes. The relative attenuation in the ultraviolet range as a function of wavelength, i.e. site‒specific spectral selectivity, decreases with increasing wavelength. Consequently, the spectral range most effective with regard to erythema undergoes the highest degree of attenuation. These findings are in accordance with radiation scatter theory. © 1997 Royal Meteorological Society.
    International Journal of Climatology 12/1998; 17(15):1697 - 1704. · 2.89 Impact Factor

Publication Stats

93 Citations
26.13 Total Impact Points

Institutions

  • 1998–2014
    • Ben-Gurion University of the Negev
      • • Jacob Blaustein Institutes for Desert Research
      • • Department of Chemical Engineering
      Be'er Sheva`, Southern District, Israel